Equalizer for stave jointers



June 11, 1929. w v, GRACE EQUALIZER FOR STAVE JOINTERS Filed Sept. 1926 2 Sheets-Sheet l INVENTOR.

W VTGrwce, I

' ATTORNEY.

June 11, 1929. j w; V, GRACE v EQUALIZER FOR S'IAVE JOINTERS Filed Sept. '7, 1926 2 Sheets-Sheet 2 1& 2.

A TTORNE Y.

Patented June 11, 1929.

UNITED I WILLIAM VIRGIL GRACE, OF COLUMBUS, MISSISSIPPI EQUALIZER FOR STAVE JOINTERS.

Application filed September 7, 1926. Serial No. 133,966.

This invention relates to stave jointer machines and more particularly to an equalizing device therefor, having for its object to provide a construction easier in operation as well as more eificient in use than those heretofore proposed. I

With these and other objects in view the invention consists in the novel details of construction and combinations of parts as will be more fully hereinafter disclosed and particularly pointed out in the claims.

Referring to the drawings forming a part of this specification, in which like numerals designate like partsin all the views,

Fig. l is a perspective View of a double jointer machine of a well known type to which this invention may be easily adapted;

Fig. 2 is a side elevational view of a jointer carriage to which the equalizing device, forming the subject matter of this invention has been applied;

Fig. 3is ahorizontal sectional view taken as on the line 33 of Fig. 2 and looking in the direction of the arrows;

Fig. at is a horizontal sectional view taken through the cross head and illustrating the assembly thereof; 4

Fig. 5 is an elevational view of the inner side of one-half of the cross head;

Fig. 6 is a side elevational view of the assembled cross head; i

Fig. 7 is an elevational view of the inner side of the other half of the cross head; and

Fig. 8 is a side elevational view of the parts shown in Fig. 5.

In the drawings, Fig. 1 represents a double stave jointer machine of a well known type having rotating wheels 1 provided with a plurality of cutting blades 2 which, in their revolutions, are adapted to form along one lateral edge of a stave blank, the curved and bevelled joint necessary, so that when the finished staves are formed into a barrel, there will be formed the tight abutting joints therebetween necessary in cooperage. The wheels and their blades are supported by a shaft3, driven from any suitable source not shown, in journals 4 carried by the side frame member-s5 which also carry a table upon which is pivotally mounted'a carriage. .At the upper corners of said carriage are pivotally secured clamps which have curved and inwardly extendingarms, the free ends of which are adapted to pass through and be slidingly held by a crosshead vertically movable in guides on said carriage. This crosshead is moved by means of a pivoted treadle provlded with an extending arm connected to said crosshead as by a reach rod. Thus it will beseen that, as the treadle is depressed, the reach rod will cause the crosshead to move downwardly in its guides, and thus'cause the inwardly extending arms of the clamps to be carried downwardly therewith. This movement of parts will cause the clamps to be rotated about their pivots so that the upper free ends of said clamps will engage the ends of the stave blankQO and hold the same in con- 1 tact with the upper portion of the carriage. Considerable diiiiculty has been experienced in actual practice with a machine of this type as well as with other well known types, due to the fact that the stave blanks sometimes are not of uniform thickness at their ends. The result is that when the treadle is depressed, one of the clamps will tightly hold one end of the stave blank, but the other clamp will not tightly engage the other end of said blank, with the result that, when the carriage is moved inwardly toward thecutters, the blank will not be formed into a perfect stave all as will be readily understood. In the continued operation of the heretofore known types'of machines, over an extended period of time, there is a large wastage of stave blanks which, being made of expensive woods, soon amounts to an appreciable financial loss. It is, therefore, to eliminate this loss and to make possible a perfect production of staves, that this invention is directed. Y

In Fig. 2 the table of the jointer machine is only frag nentarily illustrated, being represented by the numeral 25. This table carries the carriage or frame generally indicatedby the numeral 26, said frame being mounted for oscillation about the pivots 27 and 28 associated with each end of the frame at the bottom thereof. Theframe 26 is provided withthe side members 29 and 30 to the former of which is pivotally secured as at 31 the clampmember 32, and to the latter of which is pivotally secured as at 33 another clamp member 34. At thecentral portion of thevframe 26 there is provided, a pair of vertically disposed guide members'35 the upper ends of which are joined by an arch .36 hav- '-ing side extensionsBi' and 38,-the former ex tending to and connecting with the upper end of the sideframemember 29, and the latter of .which extends in the opposite direction andconnects with the upper extren'lity of the j of the crosshead 55.

other side frame member 30. By this construction there is providedfor the ends of the stave blank the bearing surface 39 associated with the clamp 32, and the bearing surface 40 associated with the other clamp member 34. The arch 36 is provided with the usual bilge pin 41 for supporting the stave blank at its mid portion.

The clamp member 32 is formed with the usual hook end having secured to the extremity thereof, as by the bolt 51, a gripping member 52 for engagement with one end of the Stave blank. The other end 56 of said clamp member is curved inwardly toward the center of the device as illustrated, but instead of passing as heretofore proposed through the center-box or crosshead, generally indicated by the numeral 55, the said end stops short of the guide 35. In said end 56 there is provided the elongated slot 57 adapted to slidingly receive the bolt 58 carried by and disposed near one end of the equalizer bar 59 centrally pivoted as at 60 to the center The bar 59 extends be yond the other side of said erosshead, and is provided near its other end with the bolt 61 adapted to slidingly engage the elongated slot 62 disposed in the end portion 63 of the other clamp, member 34, said slot 62 being in all respects similar to the slot 57 above described. The said clamp member 34 is similar in all respects to the clamp member 32, being provided with a hook end 64 having secured to the extremity thereof, as by the bolt 65, a gripping member 66 adapted to hold the other end of the stave blank against the bearing surface 40. a

l/Vith particular reference to Figs. 4 to 8 inclusive, it will be seen that the crosshead 55 is made in two parts, one part 70 illustrated in Figs. 5 and 8 and the other part 71 illustrated in Fig. 7. The part 70 comprises a main body portion 72 having formed therein from one side a recess providing the upper surface 73 and the lower surface 74, each of arcuate contour. The main body portion 72 is provided also with side extensions 75 and 76 which are adapted to engage the vertical. guides 35 of the frame 26 of the jointer carriage. A boss 77 is provided on the underside of the member 70 which is internally screw-threaded or otherwise adapted as at 78 to receivethe upper end of the reach rod 79 which may be secured to said member as by the screw 80. The reach rod 79 extends downwardly, its other end being pivotally secured, as by the yoke 81, to an extension 82 corresponding in all respects to the extension 18 illustrated in Fig. 1. The said extension 82 is carried by the rod 83 pivoted as at 84 to the machine, said rod 83 being provided with the treadle 85 exactly similarin all respects to the treadle 16 illustrated in Fig. 1.

The other part 71 of the crosshead 55 comprises, what may be termed a cap plate having both ends of the stave blank is the same.

a main body portion of the same general dimensions as the main body portion 72 of its companion part, but of much lessthickness. The part 71 is likewise provided with lateral extensions 91 and 92 which are adapted to engage-the guides 35 of the frame 26 of the machine. The two parts 70 and 71 are adapted to be secured together as by the bolts 93 and 94 passing through the holes 95 and 96 provided therefor, and said parts are centrally bored as at 97 to receive thebolt 60 forming the pivot for the equalizer bar 59.

When the two parts 70 and 71 are assembled a,

cured thereto as by the pivot bolt 60. Thus it will be seen that theequalizer 59 isfree to oscillate about the pivot 60,'said movement being permitted by the arcuate surfaces 73 and 74 of the recessed portion of the cross head. bearings for the equalizer bar when it is rocked as a result of clamping a stave having ends of unequal thickness. Inother words the bar is loosely pivoted to the cross head by the bolt 60 which is only for the purpose of preventing substantial endwise movement or displacement of said bar. Thus it will be seen that the entire thickness of the bar is made to receive the force of the pressure applied through the treadle 85 whereas in heretofore known constructions only half the thickness of the equalizer bar has received this pressure. F urther, when the bar 59 oscillates, the bolts 58 and 61 carried at the ends thereof will move either upwardly or downwardly according to the direction of oscillation, and it will still further be seen that this movement of the bolts 58 and 61 will cause either an up or a down movement of the inwardly extending slotted arms "of the clamp members 32 and 34.

In operation this equalizing device functions as follows. A stave blank, whose ends are of the same thickness, when placedover the bilge pin or central support 41 will have its ends tightly clamped to the bearing surfaces 39 and 40 by the gripping members 52 and66 carried by the clamps. the treadle 85 is depressed, the clamps 32 and 34 willbe moved equally about their pivots 31 and 33 respectively, because the thickness of In other words, the clamps being of the same size, the equalizer 59 will remain in a horizontal plane during the application of treadle pressure. 1 y

That is to say, when These arcuate surfaces constitute Should the stave blank, however, have ends of unequal thickness, it will be obvious that when pressure is applied to the treadle 85, the

center-box will be moved downwardly in its guides 35, but the equalizer will oscillate. That is to say, due to the inequality of thickness in the two ends of the stave blank, the in wardly extending end of one of the clamp members will be moved downwardly to a position in a horizontal plane below the horizontal plane passing through the inwardly extending end of the other clamp member. In other words, when said uneven stave blank is fully clamped to the bearing surfaces 39 and 40, the equalizer 59 will not be disposed in a horizontal plane. However, by this construction, the pressure applied through the treadle to the center-box 55 is equalized due to the pivoting of the bar 59 and the slots in the ends of the clamp members 32 and 34 all as will be readily understood, with the result that the stave blank with its ends of unequal thickness, will be clamped with the same degree of pressure at both ends.

Such a condition was impossible with here tofore known constructions such as illustrated -in Fig. 1, because all of the pressure applied through the treadle and the cross-head, of said figure, was exerted on only one of the clamp members when a stave blank with unequal ends was inserted in the machine. There being no pressure exerted through the other clamp, the end of the stave blank at said last mentioned clamp would not be secured at all, or would be ineffectually secured, with the re sult that the stave would be imperfectly formed.

Thus it will be seen from the above description that by this invention there is provided an equalizing device comprising the bar 59 which forms with the inwardly extending ends of the pair of clamps, a loose connection which will make possible an equal movement of said clamps when the center-box 55 is moved. This is apparent because the bolts 58 and 61 are adapted to freely and slidingly engage the slots 57 and 62 provided in the clamps, and because the bar 59 is loosely pivoted as by the bolt to the center-box 55. Thus the total amount of pressure applied through the treadle to the center-box is equally divided, each clamp receiving one-half thereof no matter whether the clamps are oscillated equally or unequally about their pivots 31 and 33.

It is obvious that those skilled in the art mayvary the details of construction as well as the arrangement of parts without departing from the spirit of the invention, therefore it is not desired to be limited to the above disclosure except as may be demanded by the claims. I

What is claimed is 1. In a stave jointer machine provided with a frame, a carriage supported thereby and a pair of clamp members pivoted to said carriage and adapted to hold the ends of a stave thereto the combination of a center-box slidingly secured to said carriage; an equalizing bar supported by said center-box and sliding ly engaging the lower ends of said clamp members; and means to move said center-box whereby said clamp members will engage said stave securely at both ends thereof; said center-box having a recess or opening through which the equalizing bar is passed, the upper and lower surfaces of said recess or opening being oppositely arched to allow rocking of the equalizer bar, one of said surfaces acting as a bearing upon which said bar rocks.

2. In a stave jointer machine provided with a frame, a carriage supported thereby and a pair of clamp members pivoted to said carriage and adapted to hold the ends of a stave thereto to the combination of a. center-box slidingly secured to said carriage; an equalizing bar supported by said center-box and slidingly engaging the lower ends of said clamp members; and means to move said eenter-box whereby said clamp members will engage said stave securely at both ends thereof; said center-box having a recess or opening through which the equalizing bar is passed, the upper and lower surfaces of said recess or opening,

being oppositely arched to allow rocking of the equalizer bar, one of said surfaces acting as a bearing upon which said bar rocks, and a transverse pin securing the bar against endwise movement while permitting the rocking motion.

In testimony whereof I affix my signature.

VVTLLIAM VIRGIL GRACE. 

